Diagnosing Bowel Cancer

If you are worried about your health you should visit your Doctor immediately.   Your Doctor will ask you some general health questions and will quite possibly examine your back passage (rectum).  


They do this by putting a gloved finger into your back passage (rectum) and feeling for any lumps or swellings.   The examination may be uncomfortable but should not be painful.  


Blood tests may be ordered to check for anaemia (which is common among bowel cancer sufferers but can also be caused by other factors), and will see if your liver and kidneys are functioning normally.  


X-Rays You may then be referred to the hospital to see a specialist Doctor or nurse for further tests and possible X-Rays.



The specialist may want to perform a sigmoidoscopy, which uses a small tube with a camera in it to look inside the back passage and the lower part of your bowel. This tube also pumps a small amount of air into the bowel to inflate it slightly so the doctor or nurse can see the bowel more clearly.  


The doctor or nurse will take samples at the same time if they see any abnormalities or polyps of the bowel lining and send them away to be examined. This whole procedure shouldn’t take any longer than about 15 minutes and you can go home immediately after.


Don’t be alarmed if you have a little bleeding from the back passage after especially if you have had polyps removed. This is normal and will clear up after a few days. You will be required to have an enema beforehand to ensure your bowel is empty.



Colonoscopy is classed as the "Gold Standard" here in New Zealand.  If you are required to have a colonoscopy, which looks at the whole bowel, the procedure will be similar to the sigmoidoscopy and can take up to an hour.


You will probably have a sedative before this test to make you drowsy as it would be uncomfortable without it.


The doctor or nurse will examine the lining of the whole length of the bowel and take samples if necessary. 


You may have to wait a couple of hours after the test before you can go home so it is best to have someone to take you home afterwards. Sometimes this procedure is covered privately through some Insurance companies in New Zealand such as Southern Cross Healthcare with certain policies.


This will save you time on the waiting list here in New Zealand which takes far too long.  In some instances patients have to meet certain criteria to be eligible for publically funded colonoscopies (I.e. first degree relative that has had bowel Cancer).

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It  always pays to check whith your health insurer what procedures can be covered by your chosen policy.


CT Colonography/Virtual Colonoscopy


CT colonography (CTC or CAT scan) are able to scan the entire abdomen and pelvis searching for polyps or cancers in the bowel.


The extent and type of bowel preparation depends on the patient's age and condition but ideally, the entire colon should be cleared usually with laxatives. You will be asked to remove all of your clothing, and will be given a gown to wear.  You will then be taken to the CT scanning room.


Carbon dioxide gas will be introduced into your bowel so that the surfaces are clearly outlined. To achieve this the radiographer will gently introduce the gas through a small tube passed into your bottom. It is the same gas that is used to make soda water, and it is extremely safe to use.


Two scans will then be performed: one scan with you lying on your back, and the other lying on your tummy. Each scan takes only a few seconds. Afterwards there will be some gas in your bowel and you may feel a little uncomfortable and bloated.  However, your body will absorb the gas very quickly so the discomfort should disappear by the time you leave the department.  


There may be some fluid or residue still in your bowel so do not stray from the access to a toilet. You may eat and drink normally immediately after the examination. The radiologist will study your images and the report will be sent to your doctor.  


Barium Enema


Sometimes a Barium enema is required which is an X-ray of the large bowel. Barium is a white liquid which is mixed with water and passed in to your back passage (rectum). You will need to hold this liquid in the rectum while the X-rays are being taken.


This liquid easily shows up any lumps or swellings on an X-ray. You will be required to have an enema beforehand to ensure your bowel is empty and will need someone to take you home afterwards. You may be constipated for a few days after the test and your first couple of stools will be white until you have passed the barium out of your system.

Lower Bowel Pill Cams


With the advent of new wearable tech trends, ingestible tech includes pills that track the health from the inside of your body and is fast becoming a revolutionary way to help beat diseases such as Bowel Cancer.


An Israeli company, "Given Imaging" a GI medical device leader, has found a way to see inside a patient’s GI tract by having them simply swallow a pill-sized camera.    


More than three million patients around the world have benefited from FDA approved pill cam capsule endoscopy with physicians being able to visualize with high accuracy the small bowel, oesophagus and colon for abnormalities.  


A small camera is placed into a pill about the size of a multi-vitamin which the patient can easily swallow. Once inside the body, the pill is able to take digital images around 4-35 frames a second inside the patient's body and transmit those images to a recording device that the patient wears around their waist.  

There is not a sufficient bowel prep available to cleanse the bowel adequately to see clearly.  Some surgeons in New Zealand fear this could cause them to miss smaller polyps or cancerous tumours so prefer to use the "Gold Standard" colonoscopies that have proved the most successful to date.


If and when an adequate bowel prep becomes available, pill cam technology will most likely overtake all current methods of screening.  Throughout the world, the technology is available to screen, administer medicine and take internal x-rays with pill cam technology.

Home Bowel Screening Kits

If you would like to be proactive with your health you can do a home based pharmacy test.

Learn about our bowel screening programme here

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